Process of constructing building-blocks.



A.'M. MI'CKELSON.

PROCESS OF CONSTRUCTING BUILDING BLOCKS.

APPLICATION FILED JULY15. i913.

Patented Feb W] T NE S SE S v of Constructing Building-Blocks, of

the following is a specification.

UNITED STATES PATENT orruon.

Pnocnss' or oons'rmrcrme BUILDING-BLOCKS.'

Specification of Letters Patent.

Patented Feb. 1, 1916;

, Application filed July 15,1913. Sei'ia1No.779,157.

To all whom it may concern:

' Be it known that I. ARTHUR M. MICKEL- SON, a citizen of the United States, residing at North Crystal Lake, inthe county of Me- Henry and State of Illinois, have invented a, new and useful Improvement in Processes which This invention relates to a process of forming an artificial building block which shall have an ornamental rough stone face, formed of pebbles or pieces of broken rock, therebygivinga wallor building the appearance of being constructed of pebbles, broken rock or comparatively small stones.

The invention consists of the novel features hereinafter described and pointed out in the claim. a The manner of carrying out the process and a sample of thefinished product are shown in the accompanying drawings, in which: I

Figure 1 is a longitudinal section through a suitable mold illustrating the preferred form of carrying 'out the process. Fig. 2 is a perspective outer face view of one of the blocks. 7

In the drawing 1, represents a suitable mold of any desired size, and upon the bottom of said mold is placed a retentive base 2, of a material of a comparatively stiff consistency when moist and plastic when more or less saturated with water, preferably clay; 3 indicates the pebbles, rocks or pieces of broken stone or any other hard-material, such as slag, with which it might be desired to face the block. The block itself is indicated at 4 and consists of any of the usual cement or concrete mixtures, either with or without coloring matter. I

The process consists in placing upon the bottom of the mold a retentive base, or par ti'ally-embedding in said base the pebbles or other facing material, and then filling in upon said material the sand and cement or other mixture of which the blocks are to be formed and packing or tamping the same to the extent desired. As soon as the block has .set sufliciently to permit its being handled it is removed from the mold and'the clay or other base material is washed ofl the face of the block, thereby leavingexposed all those portions of the pebbles, rock or other material which had been embedded in said base, and consequently protected from contact with the cement or block material. It will be noted therefore that the base forms a double purpose, first it retains in ,proper position the pebbles or facing material thereby permitting them to be grouped in any ornamental manner desired, and it also prevents the block material from working down to the bottom of the mold and thereby causing'the facing material'to be entirely embedded in the block materialn Consequently when said base is washed off the block presents a rough surface with numerous crevices between the projecting portions of the facing material fromwhich the clay or base has been removed by ,the washing process.

I am aware of the fact that it has been proposed to embed pieces of rock into ablock and'then to polish the 'same' off, and also that it is common to pebble-dash a concrete surface by throwing or otherwise embedding gravel into the face of said surface, and then washing the same down with cement. In all of these processes the block material is either forced entirely around the pieces of rock or else is filledin all of the spaces between the various pieces so that the facing material is substantially flush with the outer face. of the block, or the gravel is applied to the wall after a cement backing has been placed thereupon and as far as'possible are fully coated with cement.

What I claim is The "process of manufacturing building blocks havingarough exterior face, which consists in partially embodying pieces of rock or equivalent material in a retentive adhesive and comparatively 'stifl base, of a material plastic when .wet, tampinga concrete mixture thereupon, permitting the game to set and then washing'ofi' the said ase.

I ARTHUR M. MreKELsoN. Witnesses: e h

BENNO BANE,

S.-'W. NELSON. 

